Home | History | Annotate | Line # | Download | only in make 
      1 /*	$NetBSD: hash.h,v 1.52 2025/04/22 19:28:50 rillig Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
      5  *
      6  * This code is derived from software contributed to Berkeley by
      7  * Adam de Boor.
      8  *
      9  * Redistribution and use in source and binary forms, with or without
     10  * modification, are permitted provided that the following conditions
     11  * are met:
     12  * 1. Redistributions of source code must retain the above copyright
     13  *    notice, this list of conditions and the following disclaimer.
     14  * 2. Redistributions in binary form must reproduce the above copyright
     15  *    notice, this list of conditions and the following disclaimer in the
     16  *    documentation and/or other materials provided with the distribution.
     17  * 3. Neither the name of the University nor the names of its contributors
     18  *    may be used to endorse or promote products derived from this software
     19  *    without specific prior written permission.
     20  *
     21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     31  * SUCH DAMAGE.
     32  *
     33  *	from: @(#)hash.h	8.1 (Berkeley) 6/6/93
     34  */
     35 
     36 /*
     37  * Copyright (c) 1988, 1989 by Adam de Boor
     38  * Copyright (c) 1989 by Berkeley Softworks
     39  * All rights reserved.
     40  *
     41  * This code is derived from software contributed to Berkeley by
     42  * Adam de Boor.
     43  *
     44  * Redistribution and use in source and binary forms, with or without
     45  * modification, are permitted provided that the following conditions
     46  * are met:
     47  * 1. Redistributions of source code must retain the above copyright
     48  *    notice, this list of conditions and the following disclaimer.
     49  * 2. Redistributions in binary form must reproduce the above copyright
     50  *    notice, this list of conditions and the following disclaimer in the
     51  *    documentation and/or other materials provided with the distribution.
     52  * 3. All advertising materials mentioning features or use of this software
     53  *    must display the following acknowledgement:
     54  *	This product includes software developed by the University of
     55  *	California, Berkeley and its contributors.
     56  * 4. Neither the name of the University nor the names of its contributors
     57  *    may be used to endorse or promote products derived from this software
     58  *    without specific prior written permission.
     59  *
     60  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     61  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     62  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     63  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     64  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     65  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     66  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     67  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     68  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     69  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     70  * SUCH DAMAGE.
     71  *
     72  *	from: @(#)hash.h	8.1 (Berkeley) 6/6/93
     73  */
     74 
     75 /* Hash tables with string keys and pointer values. */
     76 
     77 #ifndef MAKE_HASH_H
     78 #define MAKE_HASH_H
     79 
     80 /* A single key-value entry in the hash table. */
     81 typedef struct HashEntry {
     82 	struct HashEntry *next;	/* Used to link together all the entries
     83 				 * associated with the same bucket. */
     84 	void *value;
     85 	unsigned hash;		/* hash value of the key */
     86 	char key[1];		/* key string, variable length */
     87 } HashEntry;
     88 
     89 /* The hash table containing the entries. */
     90 typedef struct HashTable {
     91 	HashEntry **buckets;
     92 	unsigned bucketsSize;
     93 	unsigned numEntries;
     94 	unsigned bucketsMask;	/* Used to select the bucket for a hash. */
     95 } HashTable;
     96 
     97 /* State of an iteration over all entries in a table. */
     98 typedef struct HashIter {
     99 	HashTable *table;	/* Table being searched. */
    100 	unsigned nextBucket;	/* Next bucket to check (after current). */
    101 	HashEntry *entry;	/* Next entry to check in current bucket. */
    102 } HashIter;
    103 
    104 /* A set of strings. */
    105 typedef struct HashSet {
    106 	HashTable tbl;
    107 } HashSet;
    108 
    109 MAKE_INLINE void * MAKE_ATTR_USE
    110 HashEntry_Get(HashEntry *he)
    111 {
    112 	return he->value;
    113 }
    114 
    115 MAKE_INLINE void
    116 HashEntry_Set(HashEntry *he, void *datum)
    117 {
    118 	he->value = datum;
    119 }
    120 
    121 /* Set things up for iterating over all entries in the hash table. */
    122 MAKE_INLINE void
    123 HashIter_Init(HashIter *hi, HashTable *t)
    124 {
    125 	hi->table = t;
    126 	hi->nextBucket = 0;
    127 	hi->entry = NULL;
    128 }
    129 
    130 void HashTable_Init(HashTable *);
    131 void HashTable_Done(HashTable *);
    132 HashEntry *HashTable_FindEntry(HashTable *, const char *) MAKE_ATTR_USE;
    133 void *HashTable_FindValue(HashTable *, const char *) MAKE_ATTR_USE;
    134 unsigned Hash_Substring(Substring) MAKE_ATTR_USE;
    135 void *HashTable_FindValueBySubstringHash(HashTable *, Substring, unsigned)
    136     MAKE_ATTR_USE;
    137 HashEntry *HashTable_CreateEntry(HashTable *, const char *, bool *);
    138 void HashTable_Set(HashTable *, const char *, void *);
    139 void HashTable_DeleteEntry(HashTable *, HashEntry *);
    140 void HashTable_DebugStats(const HashTable *, const char *);
    141 
    142 bool HashIter_Next(HashIter *) MAKE_ATTR_USE;
    143 
    144 MAKE_INLINE void
    145 HashSet_Init(HashSet *set)
    146 {
    147 	HashTable_Init(&set->tbl);
    148 }
    149 
    150 MAKE_INLINE void
    151 HashSet_Done(HashSet *set)
    152 {
    153 	HashTable_Done(&set->tbl);
    154 }
    155 
    156 MAKE_INLINE bool
    157 HashSet_Add(HashSet *set, const char *key)
    158 {
    159 	bool isNew;
    160 
    161 	(void)HashTable_CreateEntry(&set->tbl, key, &isNew);
    162 	return isNew;
    163 }
    164 
    165 MAKE_INLINE bool MAKE_ATTR_USE
    166 HashSet_Contains(HashSet *set, const char *key)
    167 {
    168 	return HashTable_FindEntry(&set->tbl, key) != NULL;
    169 }
    170 
    171 MAKE_INLINE void
    172 HashIter_InitSet(HashIter *hi, HashSet *set)
    173 {
    174 	HashIter_Init(hi, &set->tbl);
    175 }
    176 
    177 #endif
    178